What happened
During a normal approach to runway 22 at Catalina Airport, the pilot of a rental Cessna (type not specified) experienced a malfunction with the flap position indicator, estimating that 20 degrees of flaps were used for the landing. After touchdown, the pilot reduced the throttle to idle and attempted to flare; however, the engine continued to produce significant power, estimated between 1,200 and 1,600 RPMs, despite the throttle being in the full rear position.
The aircraft porpoised on the runway, bouncing once after the initial touchdown. In an attempt to settle the aircraft, the pilot lowered the nose, but the plane bounced three additional times. The pilot reported that the only way to stop the excess thrust was to move the mixture control to the idle cutoff position, though the engine continued to run for at least 30 seconds after the mixture was moved before finally shutting down. The aircraft sustained substantial damage to the firewall.
The investigation
Investigators examined the engine and aircraft at the operator's maintenance facility. Maintenance records indicated that the engine had been overhauled on January 16, 2002, and installed on the airframe on March 12, 2002, approximately 17 hours before the accident. The records also noted that the carburetor had been overhauled during the engine overhaul.
Upon examination of the carburetor, investigators found fuel staining from the parting surface gasket. While continuity of the power controls was confirmed between the cockpit and the carburetor, a functional test on a calibrated fuel flow test bench showed the carburetor flowed to specification and the float stopped the flow at the correct level. Disassembly of the unit revealed that the jets were clear, the brass floats were intact and correctly set, and the screws securing the bowl chamber to the body were tight.